Abstract 10397: Prevalence and Outcomes of Primary Cardiomyopathy in Marfan Syndrome

Abstract

Introduction: Cardiovascular disease is the leading cause of morbidity and premature mortality in Marfan Syndrome (MFS), with ≥ 50% of patients developing a secondary, dilated cardiomyopathy from chronic valvular regurgitation. Apart from significant valvular disease, patients with MFS have evidence of systolic dysfunction, suggestive of a primary cardiomyopathy. However, prior cross-sectional studies have been limited by small sample sizes and short durations of follow-up. Our aim was therefore to determine the true prevalence and long-term outcomes of a primary cardiomyopathy in MFS. Methods: We performed a retrospective chart review of all adult patients with a confirmed diagnosis of MFS followed at Stanford Health Care. Those with significant valvular dysfunction (≥moderate aortic or mitral regurgitation), coronary artery disease, or prior cardiac surgery were excluded. Myocardial dysfunction (MD) was defined as a left ventricular ejection fraction (EF) <55%, as assessed by echocardiography or on cardiac MRI. Genetic, sociodemographic, and potential cardiac risk modifiers were also recorded. Results: A total of 753 patients with confirmed MFS were identified and followed over a median of 8 years (IQR 4, 13). Of the initial cohort, 241 patients (47% male, 71% Caucasian) met inclusion criteria and defined the at-risk population. MD was present in 30 patients (12.4%), with a median age of onset at 32 years (IQR 24.5, 44.8), median EF of 50.9% (IQR 48.0, 53.8), and evidence of clinical heart failure (NYHA Class ≥2) in 10% of patients. There was no significant association with the majority of queried sociodemographic and traditional cardiovascular risk variables. MD was more commonly observed in patients with larger aortic root diameters (aortic root ≥ 4.0 cm: AOR=4.2, 95% CI=1.2-15.0, p=0.03); however, corresponding use of goal-directed medical heart failure therapies did not appear to be protective against the development of MD (p=0.5). Conclusions: Even in the absence of significant valvular pathology, MD is prevalent in MFS from a young age, indicative of a primary cardiomyopathy. While dysfunction is often subclinical and mild in nature, it can progress across the lifespan and appears to be refractory to standard medical heart failure therapies.